Email updates

Keep up to date with the latest news and content from Nutrition Journal and BioMed Central.

Open Access Highly Accessed Research

An amino acid-electrolyte beverage may increase cellular rehydration relative to carbohydrate-electrolyte and flavored water beverages

Chih-Yin Tai1, Jordan M Joy1, Paul H Falcone1, Laura R Carson1, Matt M Mosman1, Justen L Straight2, Susie L Oury3, Carlos Mendez3, Nick J Loveridge14, Michael P Kim1 and Jordan R Moon15*

Author Affiliations

1 MusclePharm Sports Science Institute, MusclePharm Corp., 4721 Ironton St., Building A, Denver, CO 80239, USA

2 University of Nebraska, Lincoln, NE, USA

3 Metropolitan State University of Denver, Denver, CO, USA

4 University of Northern Colorado, Greeley, CO, USA

5 Department of Sports Exercise Science, United States Sports Academy, Daphne, AL, USA

For all author emails, please log on.

Nutrition Journal 2014, 13:47  doi:10.1186/1475-2891-13-47

Published: 26 May 2014

Abstract

Background

In cases of dehydration exceeding a 2% loss of body weight, athletic performance can be significantly compromised. Carbohydrate and/or electrolyte containing beverages have been effective for rehydration and recovery of performance, yet amino acid containing beverages remain unexamined. Therefore, the purpose of this study is to compare the rehydration capabilities of an electrolyte-carbohydrate (EC), electrolyte-branched chain amino acid (EA), and flavored water (FW) beverages.

Methods

Twenty men (n = 10; 26.7 ± 4.8 years; 174.3 ± 6.4 cm; 74.2 ± 10.9 kg) and women (n = 10; 27.1 ± 4.7 years; 175.3 ± 7.9 cm; 71.0 ± 6.5 kg) participated in this crossover study. For each trial, subjects were dehydrated, provided one of three random beverages, and monitored for the following three hours. Measurements were collected prior to and immediately after dehydration and 4 hours after dehydration (3 hours after rehydration) (AE = −2.5 ± 0.55%; CE = −2.2 ± 0.43%; FW = −2.5 ± 0.62%). Measurements collected at each time point were urine volume, urine specific gravity, drink volume, and fluid retention.

Results

No significant differences (p > 0.05) existed between beverages for urine volume, drink volume, or fluid retention for any time-point. Treatment x time interactions existed for urine specific gravity (USG) (p < 0.05). Post hoc analysis revealed differences occurred between the FW and EA beverages (p = 0.003) and between the EC and EA beverages (p = 0.007) at 4 hours after rehydration. Wherein, EA USG returned to baseline at 4 hours post-dehydration (mean difference from pre to 4 hours post-dehydration = -0.0002; p > 0.05) while both EC (-0.0067) and FW (-0.0051) continued to produce dilute urine and failed to return to baseline at the same time-point (p < 0.05).

Conclusion

Because no differences existed for fluid retention, urine or drink volume at any time point, yet USG returned to baseline during the EA trial, an EA supplement may enhance cellular rehydration rate compared to an EC or FW beverage in healthy men and women after acute dehydration of around 2% body mass loss.

Keywords:
Rehydration; Fluid retention; Amino acid; Carbohydrate; Electrolyte; Hydration; Recovery